Moles Part 1 – Particles Aim CE3: How many different measures is a mole?

Intro to the Mole, the Chemist’s Dozen A mole - a given number of particles o A pair of shoes = 2 items o A dozen roses = 12 items o A mole of water = 6.02 x items or particles

A mole measures the number of particles in different samples 1 mole of iron (Fe) has 6.02 x atoms 2 moles of iron has how many atoms? 2 x (6.02 x ) = x atoms 1 mole of sulfur (S) has 6.02 x atoms How many moles of sulfur are in 8 moles? 2 x (6.02 x ) = x atoms 1 mole of water has 6.02 x molecules 5 moles of water has how many molecules? 5 x (6.02 x ) = 3.01 x molecules

1 mole of water has 6.02 x molecules How many ATOMS are in 1 mole of water? This can be answered using proportions H 2 O = 3 atoms for each molecule 3 atoms = X moles atoms 1 molecule 1 mole molecules X = 3 moles atoms How many atoms are in 3 moles of atoms? 3 moles atoms = X atoms 1 mole molecules 6.02 x molecules X = 3x(6.02 x ) =18.06 x atoms

Knowing that all moles have the same number of particles is important in chemical reactions It allows the chemist to determine how many particles will be reacting Example:2 H 2 + O 2  2 H 2 O o The equation tells us that 2 molecules of H 2 will react with 1 molecule of O 2 to make 2 molecules of water o It ALSO tells us 2 moles H 2 and 1 mole O 2 will produce 2 moles of water o Remember, 1 mole = 6.02 x particles! o That’s a lot of molecules in this reaction!

Practice 1. How many atoms are in a 2.00 mole sample of aluminum? 2. How many molecules are in a mole sample of ammonia? 3. How many atoms are in a 1.00 mole sample of the compound hydrogen bromide (HBr)? 4. How many ions are in a 4.00 mole sample of sodium chloride (NaCl)?